1. Field of the Invention
The Present Invention relates generally to a connector, and, more particularly, to a connector having a lockable engagement mechanism so as to maintain connection, even when subjected to an unexpected external force.
2. Description of the Related Art
Conventional connectors may be engaged, usually through “tight fitting,” with a counterpart connector arranged on a side wall of a casing used for accommodating an electronic device, such as a control unit. Such connectors are typically provided with an engagement lever, which has an engagement groove, disposed to be pivoted in a state where the engagement groove is mated with an engagement projection arranged on a housing of the counterpart connector. In this manner, the fitting force is increased to result in a secure engagement between the connectors. An example of a typical conventional connector can be found in Japanese Patent Application Laid-Open (Kokai) No. 2006-114357.
FIG. 28 is a perspective view of a conventional connector assembly (i.e., a connector and a counterpart connector. In FIG. 28, socket-side connector 801 is connected to an extreme end of a non-illustrated conductive cable. Socket-side connector 801 is engaged, by tight fitting, to plug-side connector 901 as a counterpart connector. Plug-side connector 901 has plug body 912, which receives plurality of plug contacts 961, and frame 911, to which plug body 912 is inserted. At an inside of each of two opposite side surfaces of frame 911, two engagement projections 918 (four in total) are connected so as to inwardly project.
Likewise, socket-side connector 801 has socket body 811, which receives plurality of socket contacts 861, and socket-side casing 821, which encases socket body 811. Socket casing 821 has opening portions 828a and 828b formed therein for allowing conductive cables to pass through. In each of opposite side walls 824 of socket casing 821, two engagement grooves 883 (four in total) are formed so that engagement projections 918 of plug-side connector 901 can be received in corresponding engagement grooves 833.
Engagement lever 881, for tightly fitting connectors 801, 901, is mounted to be engaged, at an end portion thereof, to sliding groove 815 formed between two engagement grooves 883 (formed in each of side walls 824) so that the above-mentioned end portion thereof can slide along sliding groove 815. When engagement lever 881 is pivoted to be moved from an initial position to a fitting completion position in a state where connectors 801, 901 are engaged with each other, a concave engagement portion of a non-illustrated engagement plate connected to the end portion of engagement lever 881 is engaged with engagement projections 918 of plug-side connector 901, as they are received in engagement grooves 883. Engagement projections 918 are then relatively moved along the side walls of the concave engagement portion, so that plug-side connector 901 is pulled toward socket-side connector 801 to be tightly engaged with each other by the concave engagement portion functioning as a cam groove. Moreover, engagement projections 918 are prevented from being removed from engagement grooves 883. As a result, a secure engagement can be established and maintained between connectors 801, 901.
In the state illustrated in FIG. 28, engagement lever 881 is positioned at the initial position and in tight contact with initial position protrusive abutting portion 834b formed in one of side walls 824. When engagement lever 881 reaches the fitting completion position, engagement lever 881 comes in tight contact with fitting completion position protrusive abutting portion 834a formed in one of side walls 824.
However, in the above-described conventional connector, since engagement lever 881 is not locked at the fitting completion position, engagement lever 881 may return to the initial position upon being subjected to an unexpected external force, such as an impact force or a vibration. As a result, the engagement with plug-side connector 901 might not be maintained. In particular, when the connector is mounted on a vehicle, the connector may be subject to vibration consistent with the running of the vehicle. Therefore, it is highly likely that engagement lever 881 will return to the initial position.